Set and get JSON values by path string.

pathAccess.js

const splitPath = (path)=> {
	return path
		.replace(/\[([\d]+)\]/g, '.$1')    // replace [0] with .0
		.replace(/\['([\w]+)'\]/g, '.$1')  // replace ['x'] with .x
		.replace(/\["([\w]+)"\]/g, '.$1')  // replace ["x"] with .x
		.split('.');
};

const getPathValue = (object, path) => {
	const pathSegments = splitPath(path);
	pathSegments.forEach(pathSegment => {
	  	object = object[pathSegment];
	 });
	return object;
};

const setPathValue = (object, path, value) => {
	const pathSegments = splitPath(path);
  	var key;
  	var objectTemp = object;
	pathSegments.forEach(pathSegment => {
	  	object = objectTemp;
	  	key = pathSegment;
	  	objectTemp = objectTemp[key];
	});

	object[key] = value;
	return value;
};

Object.prototype.path = function(path, value){
	if(value) {
	  	return setPathValue(this, path, value);
	} else {
	  	return getPathValue(this, path);
	}
};



// examples 

foo = {
	bar: {
		buzz: 0
	},
	fizz: [
		{
			bar: 0
		}
	]
};

console.log(foo.path('bar.buzz',1));
console.log(foo.path('bar.buzz'));

console.log(foo.path('fizz[0].bar',2));
console.log(foo.path('fizz[0].bar'));

console.log(foo.path("fizz[0]['bar']",3));
console.log(foo.path("fizz[0]['bar']"));

console.log(foo.path("",4));
console.log(foo.path(""));